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Re: APOD: A Picturesque Venus Transit (2012 Jun 03)
Posted: Tue Jun 05, 2012 4:25 pm
by neufer
Chris Peterson wrote:neufer wrote:
Au contraire mon ami 
This is clear evidence of:
- 1) the safety of windshield glass in preventing solar UV skin damage[/size]
2) the fact that our truck driver ain't British:
That he isn't British is clear. However, an interesting thing about this case is that the driver's exposure to sunlight was not through an open window, but through the side glass- which does pass UVA.
Bullsh... The window
was clearly open in the summer else the contrast wouldn't be so stark.
(Let's see his right & left arms.)
Re: APOD: A Picturesque Venus Transit (2012 Jun 03)
Posted: Tue Jun 05, 2012 4:59 pm
by Chris Peterson
neufer wrote:Bullsh... The window was clearly open else the contrast wouldn't be so stark.
When driving, you typically only receive significant sunlight through the driver's side window. Not from the front window. This condition, unilateral dermatoheliosis, is also reported in pilots. Their windows don't open.
The specific case of this truck driver is reported in
an article in the New England Journal of Medicine, which makes note that this is UVA damage caused by light passing through the glass, as opposed to UVB damage, which would be prevented by the glass. Ordinary tempered soda-lime glass of the sort used in car windows has its UV cut between 325 nm and 350 nm, meaning it passes most UVA radiation. This is easily tested if you use photochromic eyeglasses (as my wife does); they transition to dark quite nicely when exposed to direct sunlight through a car window.
unilateral dermatoheliosis
Posted: Tue Jun 05, 2012 5:34 pm
by neufer
Chris Peterson wrote:neufer wrote:
Bullsh... The window was clearly open else the contrast wouldn't be so stark.
When driving, you typically only receive significant sunlight through the driver's side window. Not from the front window. This condition, unilateral dermatoheliosis, is also reported in pilots. Their windows don't open.
- 1) A pilot's picture with such stark contrasts was not shown
(because there probably aren't any...their windows don't open).
2) Pilots fly at altitudes where there is noticeably less UVA/UVB protection from clouds, sky scattering or ozone to begin with.
Chris Peterson wrote:
The specific case of this truck driver is reported in
an article in the New England Journal of Medicine, which makes note that this is UVA damage caused by light passing through the glass, as opposed to UVB damage, which would be prevented by the glass. Ordinary tempered soda-lime glass of the sort used in car windows has its UV cut between 325 nm and 350 nm, meaning it passes most UVA radiation. This is easily tested if you use photochromic eyeglasses (as my wife does); they transition to dark quite nicely when exposed to direct sunlight through a car window.
Common sense strongly suggests that
most of the UVA/UVB damage was done with the car window open.
(As common sense strongly suggests that Shakespeare wasn't written by someone with an illiterate family.)
This was hardly a controlled scientific experiment with multiple truckers who:
- 1) do & don't use UVA/UVB protection.
2) do & don't use UVB protection.
3) do & don't use closed air conditioned trucks in the summer.
Re: unilateral dermatoheliosis
Posted: Tue Jun 05, 2012 5:43 pm
by Chris Peterson
neufer wrote:Common sense strongly suggests that most of the UVA/UVB damage was done with the car window open.
Common sense suggests no such thing to me. This is reported as UVA damage. UVA passes through window glass. A driver is only exposed to the Sun through his side window.
I have no reason at all to doubt the veracity of the article. The fact that he
doesn't show typical UVB damage supports the assertion that his exposure was through glass.
Transit of Venus Event Locations
Posted: Tue Jun 05, 2012 5:47 pm
by neufer
Re: Transit of Venus Event Locations
Posted: Tue Jun 05, 2012 6:05 pm
by Beyond
I could see my mailbox. Barely.
Re: unilateral dermatoheliosis
Posted: Tue Jun 05, 2012 6:43 pm
by bystander
neufer wrote:
Common sense strongly suggests that most of the UVA/UVB damage was done with the car window open.
(As common sense strongly suggests that Shakespeare wasn't written by someone with an illiterate family.)
Obviously, common sense fails.